On 6/6/22 18:23, enh wrote:
> i think the safest choice for bionic is probably just "disable the new
> check and preserve the old behavior".

Yes, that sounds right.

Come to think of it, that's simpler (and arguably better) on all
platforms. That is, if you give strftime a format containing %s, you
must also pass a struct tm that came from a successful localtime call;
otherwise behavior is undefined. In the undefined case tzdb strftime can
simply output (time_t)-1 for %s.

Proposed patch attached and installed into the development repository.
This doesn't affect tzdb itself, as tzdb never gets into this situation.